Despite all of the hype about video chat and circles versus lists, to me the big announcement looks like group chat - which seems kind of stupidly obvious. Thinking about it, Google may have missed the mark by throwing video into the equation - unlike is the case with video, when people don't have to get dressed to be part of a discussion based on text. It almost looks like Google heard that Facebook was working on group features and video and assumed that they would be integrated.
I may be mistaken, but I think that's part of the idea with G+; you post an update to a specific circle and you basically have a chat with that circle.
Gmail has had group chat for a long time. G+ has it on the mobile app, and really you could join a hangout and use the text chat feature for group chat as well (even without a mic/webcam). I'm not sure why the G+ in-browser gchat doesn't support group chat, but I would guess it probably will.
So it does. I have it signed out (I don't need my gchat's going to 4 different places), so I turned it on briefly and failed to notice that. Thanks for pointing that out!
